[DoNotMerge][AMDGPU][WaveTransform] special phi-elimination for i1-values

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[z1-cciauto]

PSDB Build Link: http://mlse-bdc-20dd129:8065/#/builders/10/builds/42

[z1-cciauto]

PSDB Build Link: http://mlse-bdc-20dd129:8065/#/builders/10/builds/43

[z1-cciauto]

PSDB Build Link: http://mlse-bdc-20dd129:8065/#/builders/10/builds/44